Fall 06 Organic I Final Exam 200pts (graded as 300pts) Name If you

Fall 06 Organic I Final Exam 200pts (graded as 300pts) Name If you do not want your graded exam placed in the box outside my office, then please tick here 1) (6pts total) Give one definition of ORGANIC CHEMISTRY. b) What makes each element unique? c) What is the requirement for a covalent bond to be considered polar? 2) Briefly explain what is meant by the following terms:(16pts total) Free radical Chiral Molecule Racemic Mixture Rate Determining Step Syn Addition Mechanism Kinetics Terminal alkyne

Fall06org1final Page 1

3) Name the classes of compound that the following molecules belong to (E.g. alkane,

amide, etc). (18pts)

O

RR

O

O-HRR S-H

R OR

O

R OO

H

O

RO

OR

RO

R

RO

HPO

O OHOH

R

4) Draw Lewis structures (sticks for bonds, and dots for lone pairs) for the below three

molecules. (9pts) (a)

(b)

(c)NH2

CH2Cl2

CH2CHF


5) For the below molecule: (8pts)

OH

H

NH2

BrFN

How many sp hybridized carbons? How many sp2 hybridized carbons? How many Hydrogens? How many chiral centers? 6) Classify each of the following reactions as an Elimination, Addition or Substitution. (5pts)

(c)

(d)

(b)

(a)

(e)

CH3H3C

OH

H3CH

Cl

Cl

HCH3CH3H3C

PhH

Br

Br

HPh

H Ph

HPh

H3C

CH3F

H

H3C CH2OHOCH3

H


7) Explain why in this electrophilic addition reaction, none of product A is generated, and product B is formed exclusively. Your answer should include curly arrows (and also someone’s name that starts with M) to receive maximum points! (9pts)

F

H

H

CH3

H-FH-F

Product BProduct A

X CH3HH

H

F

CH3

8) Draw an energy level diagram for a typical exothermic E1 process. Make sure to label (a) the axes (b) the reactants and products (c) any transitions states (d) ΔHo for the overall reaction (e) the rate determining step (9pts)


9) By considering the hybridization of the central atom, predict the shape and bond angles of H3O+. (5pts) 10) Name the following molecules in IUPAC form. (15pts)

(c)

(d)

(b)

(a)

(e)

CH3

CH2CH3Br

I

OH

Cl

CH2CH2CH2CH2CH3H


11) Assign R or S to each chiral center in these molecules. (12pts)

Cl

HO CH3F

CO2HHClHH

CF3

Cl

H

CH2

F

F

(c)

(d)

(b)

(a)

O

O

NHCH3

CH3H

HH

12) What is the name of the type of Projection used in part (d)? (2pts) (b) Who invented the priority convention for assigning R and S to chiral centers? (2pts)


13) Explain mechanistically the observation that when Br2 is added to cyclohexene, the Bromine atoms end up anti to one another. (10pts)

Br-Br BrBr

anti dibromide 14) Draw the lowest energy conformation of propylcyclohexane. Also name the conformation of the ring, and the position of the propyl substituent. (10pts)


15) State two facts about a σ bond, and two facts about a π bond. (4pts) b) State two characteristics of an E2 reaction. (2pts)

c) State two characteristics of an SN1 reaction. (2pts)

d) Define structural isomers, and stereoisomers. Provide an example of both types. (6pts)


16) Give the reagents for 5 of the 6 following reactions of methylcyclohexene. (15pts)

O

Br

OH

Br

BrOH

16b) Write the mechanism for one of the above reactions. (10pts)


17a) Give the products in 5 of the 6 following transformations. (15pts)

OH

PCC

H2CrO4

PBr3

1) Na2) CH3CH2CH2Br

1) Pyridine, Tos-Cl

H2SO4

H3C-C C- +Na2)

17b) Write the mechanism for one of the above reactions. (10pts)


***BONUS QUESTION (1 pt per correct answer, maximum = 6)*** Draw all the different isomers of C5H10 that contain zero π bonds.


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Fall 06 Organic I Final Exam 200pts (graded as 300pts) Name If you